NHS medicines database (dm+d)
NHS medicines database (dm+d)
The NHS Dictionary of Medicines and Devices (dm+d) is the NHS standard dictionary for medicines licensed in the UK. Electronic systems that exchange or share information about medicines relating directly to a patient’s care must adhere to this standard by using dm+d identifiers and descriptions when transferring information.
dm&d is a cornerstone of the Electronic Prescription Service. dm+d provides a unique code for each medicine and device along with a textual description of the item and as both pharmacy and prescribing systems have adopted dm+d, it supports interoperability by allowing these diverse clinical systems to ‘talk the same language’.
The dictionary is structured around four key components: Virtual Medicinal Product (VMP), Actual Medicinal Product (AMP), Virtual Medicinal Product Pack (VMPP) and Actual Medicinal Product Pack (AMPP).
The Virtual Medicinal Product (VMP) describes the generic title for a product including the form and strength, for example ‘Atenolol 100mg tablets’.
The Virtual Medicinal Product Pack (VMPP) describes the generic title for a generic or proprietary product pack which is known to have been available. The description includes the pack size, for example ‘Atenolol 100mg tablets 28 tablet’.
The Actual Medicinal Product (AMP) describes an actual product which is known to have been available linked to the name of a particular supplier, for example ‘Tenormin 100mg tablets (AstraZeneca UK Ltd)’.
The Actual Medicinal Product Pack (AMPP) describes an actual product which is known to have been available linked to both the name of a particular supplier and information on the pack size of the product, for example ‘Tenormin 100mg tablets (AstraZeneca UK Ltd) 28 tablet 2 x 14 tablets’.
Linked to each component, the dictionary also includes information to support the prescribing and dispensing process, for example linked to the ‘Actual Medicinal Product Pack’ component there are a range of attributes detailed such as the product’s legal category and confirmation of whether a product is considered a special container or calendar pack. This information is populated by the Pricing Authority.
It is estimated that dm+d contains over 99.9% of medicines and appliances prescribed in primary care. Items not included in dm+d include certain extemporaneously dispensed and special formulation products. If a GP wishes to prescribe a medication item which is not listed in the dm+d, an electronic prescription cannot be issued by EPS and current paper prescription processes should be followed.
NHSRxS work to ensure licensed products are on dm+d by product launch date, however it may still take time for an individual system supplier to update their systems with the latest release of dm+d; typically, suppliers update their systems monthly.
Mapping of system supplier drug databases to dm+d
A prescriber will issue a prescription for a product via the EPS service using either the VMP or AMP code.
System suppliers currently use a variety of drug databases in their systems, in some cases these are maintained in-house, in other cases a supplier may purchase their database from an external company. where a supplier has not adopted the NHS dm+d as their core database, they must ‘map’ the codes of the individual products on their database with the dm+d to send messages via the electronic Prescription service. Electronic messages will contain the dm+d codes and descriptions even where a supplier has adopted a mapped solution.
An issue that may arise is that if an individual GP system supplier has not mapped a particular item held on their drug database with the dm+d code, that GP may not be able to prescribe that item electronically. The current requirement on GP system suppliers to undertake at least 95% mapping of their drug databases to dm+d based on the most frequently prescribed drugs in primary care. This equates to just over 2100 products. The dm+d and EPS Programmes will continue to work with system and drug database suppliers to ensure the level of mapping increases and is maintained when new products become available in England.
It is essential that mapping is accurate. If whilst dispensing a prescription via the service, a pharmacist identifies an incorrect map, for example if the information printed on the token is different from prescribing information shown on the screen, the pharmacist should report it to their system supplier immediately. The incident should also be reported to the National Patient safety Agency (NPSA) using their online reporting form.
Changes that pharmacy staff may notice
Depending on what functionality has been available historically in a particular system, where dm+d has been adopted, as the information in dm+d is sourced from the NHSRxS database, pharmacy staff may notice improvements in the accuracy of dispensing and endorsing guidance provided by the systems. For example information on whether a product can be prescribed on an NHS prescription. Different suppliers are likely to make use of this information in different ways.
Other changes that staff may notice:
Word order: Staff may also notice a change in the description of products in their systems with products listed in dm+d described according to the dm+d editorial policy. For example, dm+d describes products in the order: product, strength, formulation. Some pharmacy systems have traditionally described products in the order: product, form, strength.
Word conventions: In some cases dm+d may use different words to those found historically in prescribing and dispensing systems. For example ‘enteric coated’ tablets are described as ‘gastro-resistant’, and for inhalers, dm+d uses the term ‘dose’ as opposed to ‘actuation’, ‘inhalation’ or ‘puff’.
Terminology length and abbreviations: In some cases, the descriptions defined by dm+d are much longer than the titles used in existing supplier drug databases, this could mean space pressure on paper outputs. In some cases, it will not be possible to print a product’s full name on a dispensing label because of space restrictions; in this case, the system may automatically abbreviate the name of the product to fit on the label. For many products, dm+d includes both the full name and an abbreviated name for this purpose.
Pick lists: As well as noticing subtle changes in the description of products, pharmacy staff may also notice that the location of products on ‘picking lists’ in systems changes depending on how a supplier has implemented dm+d within their system. Also in some systems, the description of a product on-screen may be subtly different from the description used in the picking list, for example where a supplier has chosen to abbreviate information in picking lists.
Quantities and units of measure: For inhalers, dm+d expresses the number of doses contained within each inhaler, for example rather than the prescription requesting ‘1 inhaler’, the prescription may read ‘200 dose’.
Key information held in the dm+d can be accessed online through a special viewer on the NHSRxS website (accessible via www.dmd.nhs.uk – select browse the dm+d). Datapharm (in collaboration with the NHSrxS) have also launched a dm+d browser which provides easy access to the dm+d information, this can be accessed online at dmd.medicines.org.uk .
The dm+d can be a useful source of information to pharmacists providing information on a product’s attributes, for example whether a particular product is reimbursable, whether broken bulk can be claimed or whether the product is recognised as a special container or calendar pack. However, it is important to note though that as different systems suppliers have implemented dm+d in different ways, the online viewers may contain more information that is available through pharmacy systems.
As the reimbursement rules can be impacted by the way a particular dispensed product has been prescribed or other items on the prescription form, care has to be taken in interpreting the information on dm+d. Common queries relate to:
- Reimbursement price of the product:
dm+d provides indicative prices for actual products. If a product is in Part VIII and prescribed generically, reimbursement is based on the Part VIII price and not the list price of the actual product dispensed.
- Indicative nature of the prices:
Prices on dm+d are extracted from the NHSRxS database, however as prices in the market change the indicative price may differ from the actual price used to calculate reimbursement. For example where the price of a generic medicine (other than Part VIII Category M) changes before the 8th of the month, the reimbursement price will be changed with effect the 1st of that month. It is also important to keep in mind that there may be a time lag between a price changing, dm+d being updated and the latest release of dm+d then being added to pharmacy systems.
- Schedule 1 products (aka blacklisted products):
Subject to the prescriber having the appropriate prescribing rights, any food, drug, toiletry or cosmetic may be prescribed on an NHS prescription unless the product is listed in the schedule 1 to the NHS (General Medical services Contracts) (Prescription of Drugs etc.) Regulations 2004 which is reproduced in Part XVIIIA of the Drug Tariff). As an exception to this rule, Schedule 1 products can be dispensed where a product is prescribed generically and the generic product is not listed in schedule 1 and the name of the product has a recognised ‘official title’. Therefore it may still be possible to dispense certain actual products where the schedule 1 field in dm+d is marked ‘yes’.
dm+d and automated calculation of reimbursement at the Pricing Authority
When a prescription is priced by the Pricing Authority, payment is based on the prescribed product and the prescription is checked for any pharmacy endorsements where further information is needed such as pack size information or information on the product supplied if the product is not in Part VIII of the Drug Tariff.
As EPS Release 2 is introduced, payment of electronic prescriptions will be based on the product, sent as a dm+d code, listed in the product field of the message. Where additional information is required to price the prescription, this will need to continue being provided by the pharmacy but through endorsements in the electronic message sent to the Pricing Authority rather than hand endorsements on a paper form.
A problem at present is prescribers including supplementary product information, for example a brand or manufacturer’s name or an indication that a sugar free or preservative free prescription is required as part of the dosage instructions rather than beside details of the prescribed product, for example:
10ml Hypromellose 0.3% eye Drops Insert one drop into both eyes Four Times a day Preservative-Free
As reimbursement of electronic messages will be based on prescribed product field, where supplementary product information is included in the dosage instruction field, this could lead to incorrect payment. If this occurs with electronic prescriptions, the prescriber will need to be informed so that the prescribed item can be cancelled and a new prescription for the correct item issued, as appropriate. There is also a risk at present of this information being overlooked on paper prescriptions priced via NHSRxS prescription processing systems. For paper-forms, contractors are advised to include any affected items in the red separators when submitting the forms to the Pricing Authority to ensure that all information is captured and the prescriptions are priced correctly.
PSNC input into the dictionary
PSNC has liaised with the DM&D Editorial Board on a number of issues relating to the Dictionary’s editorial policy and how particular products are represented in the Dictionary Structure. PSNC is monitoring the implementation of the Dictionary and will continue to raise issues as necessary with the NHS Digital and the Pricing Authority.
Related project: Standard dosage syntax
The DM&D is providing a standard description and electronic identifier for all medicines but at present there is no standard structure to represent dosage instructions, for example, “Take two tablets three times a day.” Without this standardisation, this information can only be sent and stored electronically using ‘free text’/text strings.
Consideration has been given to developing a ‘dosage syntax’ so that this information can be sent in a standard coded format, which will enable diverse clinical systems to manipulate the data transferred, for example calculate a dose or quantity. This will also improve patient safety by standardising the way that dosage instructions are communicated and reducing the potential for misinterpretation.
The dosage syntax model was developed by the NHS Information Authority in conjunction with the international health standards organisation, HL7. This work is currently on hold due to resource constraints. PSNC believes it a priority to finalise and implement the standard dosage syntax.